The distribution of the most frequent enteroparasites in the population of Assis, State of São Paulo, was studied from 1990 to 1992. A total of 18,366 medical examinations from six sanitary care centers in the neighbourhoods of Marialves, Progresso, city center, Xavier, Fiúza and Bonfim were analized. The general prevalence of enteroparasites was 23.3%. The most frequently found enteroparasites were: Giardia intestinalis (8.7%), Ascaris lumbricoides (5.5%), Trichuris trichiura (2.4%) and Hymenolepis nana (1.9%). In Marialves, a low income neighborhood, the prevalences were: 17%; 13.1%; 5.9% and 4.2%, rspectively. The age group from 3 to 12 years showed the largest number of infected individuals. There was a correlation between basic sanitation conditions, expressed as the number of places connected to the city water and sewage systems, and the prevalence of parasites. There was also a decrease of parasite prevalence in all sanitary care centers from 1990 to 1992, which coincided with the increase in the number of new water and sewage systems in these neighborhoods.
Enteroparasitosis; Prevalence; Sanitation; Epidemiology